A whiff of air frozen in ice for 1 million years provides a new snapshot of Earth's ancestral climate.

Scientists uncovered the ancient climate record from Antarctic blue ice. The ice core was drilled from a region called the Allan Hills, about an hour by plane from the McMurdo research station. Bubbles inside the ice are tiny windows into Earth's former atmosphere. Gases such as carbon dioxide and methane were trapped and preserved inside the bubbles when snow fell in the past.